The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 09, 1996
Filed:
Feb. 15, 1995
Applicant:
Inventor:
Tsukasa Ogino, Yokohama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4434 ; 369 4432 ; 369 4428 ; 369 4435 ;
Abstract
The present invention provides an optical information recording and reproducing apparatus wherein a light beam spot is properly illuminated onto a recording medium by detecting a tracking error signal and/or a focus error signal in a time shared mode and by activating a tracking actuator and/or a focus actuator, thereby performing the recording and reproducing of information. The apparatus of the present invention includes a device for approximating an error signal on the basis of a plurality of error signals previously detected, when an error signal cannot be detected during an error signal detecting operation.